From cb181d6f916c85690f21b3e01f321614f00e8f4d Mon Sep 17 00:00:00 2001
From: Gabe Black <gabeblack@google.com>
Date: Tue, 6 Jan 2015 22:13:56 -0800
Subject: [PATCH] cpuid, x86: Revert "Enabling more features in CPUid"

That change enables CPUID bits for features that aren't implemented in gem5.
If a simulated system tries to use those features because it was told it
could, bad things can happen.
---
 src/arch/x86/cpuid.cc | 18 ++----------------
 1 file changed, 2 insertions(+), 16 deletions(-)

diff --git a/src/arch/x86/cpuid.cc b/src/arch/x86/cpuid.cc
index de11195e0..f3f9a82d7 100644
--- a/src/arch/x86/cpuid.cc
+++ b/src/arch/x86/cpuid.cc
@@ -96,15 +96,8 @@ namespace X86ISA {
                         stringToRegister(vendorString + 8));
                 break;
               case FamilyModelSteppingBrandFeatures:
-                /** Features Enabling
-                 * rdx, enabling most of the features except:
-                 * FXSR, FFXSR, Page1GB in EDX
-                 *
-                 * rcx, disabling most of the features except:
-                 * SSE4A, XOP, FMA4 in ECX
-                 */
                 result = CpuidResult(0x00020f51, 0x00000405,
-                                     0xe3d3fbff, 0x00010840);
+                                     0xe3d3fbff, 0x00000001);
                 break;
               case NameString1:
               case NameString2:
@@ -160,15 +153,8 @@ namespace X86ISA {
                         stringToRegister(vendorString + 8));
                 break;
               case FamilyModelStepping:
-                /** Features Enabling
-                 * rdx, enabling most of the features except:
-                 * HTT in EDX
-                 *
-                 * rcx, disabling most of the features except:
-                 * SSE3, SSSE3, FMA, SSE41, XSAVE, AVX in ECX
-                 */
                 result = CpuidResult(0x00020f51, 0x00000805,
-                                     0xe7dbfbff, 0x14081201);
+                                     0xe7dbfbff, 0x00000001);
                 break;
               default:
                 warn("x86 cpuid: unimplemented function %u", funcNum);
-- 
2.30.2